''Almasaurus'' is an extinct
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...
of
trematosaurian
temnospondyl
Temnospondyli (from Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') is a diverse order of small to giant tetrapods—often considered primitive amphibians—that flourished worldwide during the Carb ...
within the
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
Latiscopidae. It is known from several skulls and some postcranial material found from the
Argana Formation
The Argana Group is a Permian to Triassic geological group in the western High Atlas northeast of Agadir, Morocco. Sometimes known as the Argana Formation, it contains eight geological members often divided into three formations. They include ...
in
Morocco
Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria ...
, which dates back to the
Late Triassic
The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch ...
.
When it was first named in 1972, ''Almasaurus'' was placed within its own
superfamily, the Almasauroidea.
Although the related latiscopid ''
Latiscopus disjunctus'' possesses
exoccipital
The occipital bone () is a cranial dermal bone and the main bone of the occiput (back and lower part of the skull). It is trapezoidal in shape and curved on itself like a shallow dish. The occipital bone overlies the occipital lobes of the cer ...
s that are underplated (a feature that suggests that it is a member of the family
Trematosauridae)
''Almasaurus'' is not considered to be a trematosaurid because it lacks such underplating.
''Almasaurus'' was considered to be a
capitosaurian by Warren & Black (1985) because it shared several characters with the group, including a deeply notched
squamosal and a
lacrimal flexure, while supposedly exhibiting none of the characters associated with trematosaurians.
[ However, more recent studies have concluded that ''Almasaurus'' is either a temnospondyl more basal than the clade formed from the dichotomy between Capitosauria and Trematosauria]Metoposauridae
Metoposauridae is an extinct family of trematosaurian temnospondyls. The family is known from the Triassic period. Most members are large, approximately long and could reach 3 m long.Brusatte, S. L., Butler R. J., Mateus O., & Steyer S. J. ...
, perhaps being a sister taxon
In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree.
Definition
The expression is most easily illustrated by a cladogram:
Taxon A and ...
of it.cladogram
A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ...
showing the phylogenetic position of ''Almasaurus'', from Schoch (2008):[
]
See also
* Prehistoric amphibian
This list of prehistoric amphibians is an attempt to create a comprehensive listing of all genera from the fossil record that have ever been considered to be amphibians, excluding purely vernacular terms. The list includes all commonly accepted g ...
* List of prehistoric amphibians
This list of prehistoric amphibians is an attempt to create a comprehensive listing of all genera from the fossil record that have ever been considered to be amphibians, excluding purely vernacular terms. The list includes all commonly accepted g ...
References
External links
''Almasaurus''
in the Paleobiology Database
The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms.
History
The Paleobiology Database (PBDB) originated in the NCEAS-funded Phanerozoic Marine Paleo ...
Triassic temnospondyls of Africa
Early Triassic amphibians of Africa
Fossil taxa described in 1972
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